This recipe is from Shirley McNevich's Mom's Best Recipes Vol 5. Published here with her permission.
Don't forget to check Shirley's blog.
(by Aunt Eileen [Knouse] Carter)
1 3/4 cup flour + 1/3 cup flour
2 1/2 cups white sugar
2 tsp. cinnamon
1/2 tsp. salt
1 3/4 sticks refrigerated butter (cut into pats)
1lb. fresh or frozen blueberries (thawed and drained)
1lb. fresh or frozen raspberries (thawed and drained)
1lb. fresh or frozen blackberries (thawed and drained)
2 tsp. vanilla
In a bowl add 1 3/4 cup flour, 1 1/4 cups white sugar, cinnamon and salt--stir
lightly until mixed. Add the butter pats--mix with a pastry blender (or a fork)
until crumbs are formed. Grease a 9 x 13 glass baking dish. Press 1/2 of the
crumb mixture into the bottom of the greased dish. In a separate bowl add
blueberries, raspberries, blackberries, vanilla, 1/3 cup flour, and 1 1/4 cups
white sugar--use a large serving spoon to carefully stir the mixture so the
berries don't fall apart. Spoon the berry mixture over the crumb mixture in the
serving dish. Sprinkle the rest of the crumb mixture over the top of the
berries. Bake at 350 degrees for 40-50 minutes or until the top is browned.